Partial clog, maybe? We had this problem, the clog was further down than the P trap. My personal opinion is that it was lint build up so we use a screen on the end of the drain tube, now.

this is all brand new, never been used pipe. of course it it possible, but not sure bow it could be clogged

Does the discharge water take a turn at that T in pic 3? If so, I believe it should be a Sanitary T to impel the water in the right direction.

JM$.02W

2" is plenty big enough. Have you run a snake through it? Sometimes things get trapped in new piping while being built. I'm not understanding the 2nd picture. What is going on there? Seems Strange.

sorry my other picture did not load. please see below drawing

2nd pick is looking down from loation 1 to the p trap
3rd is the run to sloped piped to main line

That drain hose looks air tight. If so, you need an air gap between hose and drain pipe to prevent a vacuum.

Looks like a 1" flex line stuffed into a 2" hole.

The tee at the bottom of this assembly is pointed in the right direction? How long is that horizontal run and is it pitched? Take the cold water hose off and point it directly in the drain hole and observe what happens.

pointed in the right direction. hard to tell what the pitch is. will try to get a small level down there tonight.

the water fill up quick. seems it doeent get past the p trap quick enough. as soon as the water is turned off, it makes a "burp/gurgle" sound and drains right through. once water goes in it backs right back up.

the drop from 1 to 2 is around 2 ft, from 2 to 3 is prob between 3 and 4 ft.

a licensed plumber did who has been in business forever did the job. I also had inpesctions done by the local plumbing dept to fulfil the permit... this isnt the first issue we are having with the plumber though so who knows..seems his work might be shoddy.

anyway to fix the issue or confirm it is a venting issue?

So this can be a clog... but the sounds that you are talking about sound like a vent problem.

Vents allow two things to happen:

1. It lets air that is ahead of the water escape so that the air doesn't block the water from draining

2. (most important) it allows air to enter so that siphon action is prevented that would pull the water out of the trap. You need water in the trap to form a seal from sewer gases entering the building.

The "burp" sounds like #1 above isn't happening - preventing the water from draining until it burps.

It also looks like this is 2" reduced down to 1.5" (although it's really hard to tell)

That pipe that comes off the tee and goes up should be a vent. I suspect that you will find it's a venting problem.

I vote venting issue as well. Stand pipes should be at least four feet tall before any other attachment at the bottom. Is it tall enough?

Burping is almost always an airlock which indicates a venting problem.

lots of people have been doing shoddy work for decades. Time in business means nothing. If this is new construction it needs to be fixed by the plumber. This also should have been checked by the inspector before you got occupancy.

so the issue was with a check valve. it wasn't opening up properly and caused the backlog.

thank you everyone for the advice and knowledge. much appreciated!

Check valve where?

Maybe Chris is referring to an "air admittance valve" which likely would have been on top of that vertical pipe that is shown between positions #2 & #3 in his drawing above?